Metallurgical process for the extraction of metals from their ores and the conversion of iron into steel.



G. H. BENJAMIN.

METAL'LUEOIOAI. PEOOESS EOE THEJEXTRAOTION OE METALS PROM-THEIR OONVEESION- OE IRON INTO STEEL. LIOATION IIL'D DEO.26,1902.'

ONES AND TEE 'SHEETS-SHEET 1 Flai.'

J 'F1G.2. g

r .H .2 lum l, I 0 1 5 4/ f NIW! 7 v Ih! c 30 WIINISSES:

No. 834.656. TA-TENTED 00T. so, 190e.

i E. H. BENJAMIN. METALLUEGTCAL PEobEss EEE 'TEE EXTEAGTION 0E METALS EEoM THEIR `ONES AND THE GGNVERSITON 0E TRON INT0 STEEL. j

` APPLICA-@fidi tiLiD" 15110; 26,1902. 2 SHEETs-SHEET 2- "Ilm UNIT-ED STATES rnarnisrrI onirica.

oEoReEH. BENJAMIN. or NEW YORK, N. Y.

METALLURemAL PROCESS rOR THE ExTRAcTloN OF METALS FROM THETR OR'Es ANO rTRE CONVERSION f OF |RON INTO STEEL. y

To all whom, it may concerm' Be it known that I, GEORGE H.BEN.TAMIN,

' a citizen of the United States, residingI atew -Iol -the process New York city, county and State:` of York, have invented certain ynew vand useful improvements in a new metallurgical process f under treatment or with the flux employedfas, for instance', adding carbon toK me; the utilization of the generated gases to effect the rimary heating of the ore bodies before such odies'- are carried `into the zone of/highest temperature employed 'in the metallurgical operations, &c. l l The object' of my invention is to reduce the cost of the metallurgical operations involved in extracting a metal from its ore or in producirig the 'composite bodies mentioned, and, 1 further,v to convertthe y L cially-.valueless slags into valuable bodies.

gtionsf. extraction of iron, copper, nickel,fand prac- My invention, considered broadly',fmay be 'used in a'large variety of metallurgical'opera- For instance, it may be used in the ltically all of the metals from their ores.

` It may also be used inI theproduction of steel or the combination of steel and other metals-such as nickel-steel, aluminium-steel,

and man anese-steel--and all combinations Where a high temperature is required to bring.

the; bodies together.' f.

lcombinations of-carbon. v

I Wish it`understood that I do not limit myselfl in any-Wisel to-the above-stated uses,

as otherA uses are possible' beyond those stated.

. To. carrymy l structure .which Will now describe, and I Wish `it understood that I claim such furnace structure yas a partl Specificatonof Lettershlnatent. v Applicationjila/d December 26, 1902. Serial No. 136,566.

heretofore commerchamber..

My invention may also be used in the production of glass, calcium4 carbid, and other invention into effect, I may lmake use of the'furnace fects ofone or more electric arcs.

. Patented oca so, 190e.

v Other furnace structures, however, may be used for carrying my invention into effect. 1

of my invention.

Referring to ther drawings, Figure 1 is a vertical section through such furnacestructure as I may use. F1g. 2 is a section taken on the line a a of Fi 1. Fig. '3 is a section taken on the line b of Fig. 1. Fig. 4 is a section taken on the linee c of Fig. 1. Fig. 5 is a sectionl taken on he line d d of Fig. -1.` Fi 6 is a section taken on the line e e of Flg .1.

irilar numerals indicate like parts. 1` -In the drawings, 10 indicates acalciningchamber, which may be of any suitable construction, preferably, however, having an innicating with the top of the chamber; 13, a reciprocating rake for moving the material along the hearth of the calcining-chamber. The calcining-chamber 10 is adapted tov discharge into a reducing-chamber 14 through an opening 1-5 in the roof of such chamber. The reducing-chamber is shown as havin an inclined'hearth 16 'and at its upper en an arched roof 17 of considera e' vertical height above the hearth; I do not, however, l

limit vmyself to the described4 in'any wise construction of the reducing-chamber.

1@ indicates a door through which access .may be obtained to the-interior of the reducing-chamber. r

'Ihe reducing-chamber 414 discharges intoj' a vertical' chamber 19. (Best shown in Fig. 3.) This chamber I denominate the 'electric This"v chamber (gradually inf creases in Width from above ownward and Vclined hearth 11; 12, a feed-hopper commuis divided into four passage-ways 20,'-in the sides of Awhich vare located op osit'ely-di's-A posed electrodes 21, 'as shown in ligi. The electrodes 21 ma be formed ofcar packed vbodies o conducting material and may receive their current from any' suitable source Aof electric ener y-*for instance, from a dynamo-electric mac yne 45. Three sets of electrodes are shown in eachpassage. I do not limit myself in any wisehto the character of the electrodes or tothe number of electrodes orto theinexact disposition in the passage, provided A.they be so placed that thematerial-treatedin passing from the reducingchar'nber through t tric chamber is subjectedv to the physical-efon rods, carbon, or other granular e elec- 'the passages 20 -of Ithe electric chamber discharge into a basin 22, (shown as somewhat'wider rio than the electrical chamber 19,) which basin may have a hearth 23, of any suitable character*that is, I may make the hearth in the ordinary manner, as is usual with reverberatory furnaces, of sand, clay, or other suitable materials, or I may make the hearth of materials which will combine with the metal under treatmentthat is, the hearth may be an acid hearth or a basic hearth, as desired.

The basin 22 communicates with the reducing-chamber 14 through a flue 24, which flue serves to carry the radiated heat and gaseous products set free from the material deposited in the basin 22, as also a portion of the light gases generated under the influence of the electric arcs, to the reducing and calcining chambers and thence to the chimneyflue 25. 26 is a damper in the chimney-flue.

Located at a lower plane than the basin 22 is an inclosed chamber 27. This fhaoiberis preferably formed with a high roof 26 and a removable hearth 29. The front of the chamber 27 has a door 30,'through which the hearth may be removed. The hearth 29 is shown as mounted en a truck to facilitate its handling. Connected to theihearth 29 is a pipe 31, through which air maybe introduced through openings 32 in the bottom of the hearth.

I do not limit myself to the employment of a removable hearth. A fixed hearth may be used, and the hearth may be otherwise modified.

Situated between the basin 22 and the oxi dizing-chamber 27 is a trough-like passage 33, (best shown in Fig. 5,) on the forward end of which is a spout adapted to discharge into the cavity of the hearth 29.

f It will be observed from Fig. 5 that the opposing faces of the electric chamber 19 and the chamber 27 are separated. The object of this is to allow access through the removable doors 34 to the trough-like passage 33.

35 indicates a plug of clay or other male` rial which may be inserted in the trough-like passage 33 to stop the flow of melted material from the basin 22 into the tank 29.

Floating in the material in the basin 22 is a clay ring 36, which serves to prevent the lighter material, such as the slags, from flowing down the trough-like passage 33 onto the hearth 29.

The top of the chamber 27 is connected, through a flue 37, to the reducing-chalnber 14, calcining-chamber 10, and stack 25.

It will be observed from the description so far as given that thel heat and gases set free in the chamber 27, the basin 22, and the electric chamber 19 all flow through the reducing-chamber and calci ning-chamber on their way to the chimney-stack, and hence serve to effect the preliminary heating and reduction of the material under treatment before it reaches the electric chamber 19.

Located immediately over the electric chamber 19 is a feed-hopper 3S, which feeds upon a hearth 39, over which moves'a reciprocating rake 40. The hearth 39 is adapted to discharge the material deposited through the hopper 3S through the passage 41 immediately into the electric chamber 19, from whence it moves with the material discharged from the reducingechamber 14 down the passages 20 and between the electrodes 21. Any suitable means may be employed to aid in heating the reducing-chamber 14, the chamber 27, and basin 22. Preferably I employ hydrocarbon-burners. Such hydrocarbon-burners 42 are shown arranged in the top of the chambers 14 and 27 and adapted to discharge their flames in a downward direction. They may otherwise be arranged. Corresponding burners are arranged on opposite sides of the basin 22 and adapted to discharge their flames horizontally across the chamber.

44 represents doors in the front and back of the basin 22 near its ends, through which any portion of the material under treatment within the basin may be extracted.

My general process and mode of operation of furnace is as follows: Assuming that iron ore is to be converted into pig metal, the orc is introduced through the hopper 12 and passes on to' the hearth 1].k of the calciningchamber 10.y IIere it is subjected to the rcquired caleining temperature, which is comparatively low relative to that of the shambers 141, 19, and 27, and parts with its moisture, which escapes, together with the products of combustion, through the chimney 25. Under the action of the rake 13 the calcined ore is moved forward and drops int-e the reducing-chaniber 14 through the passage 15. lIere the ore is subjected to a reducing atmosphere created by the .heat and gases arising from the electric chamber 19 and the chambers 22 and 27, and, further, if required, the temperature, as well as the character of the atmosphere within the chamber 14, may be altered or modified by thc introduction of gas and air. As the ore is reduced it flows toward the month of the electric chamber 19. The ore while in the rcducmg-chamber occupies approximately the situation represented by the dotted lines, and thc ore may, if desired, be fluxed by the addition of lime or other material introduced through the door 1S. Preferably, however, the flux is introduced through the hopper 3S. I may infrodnce at this time lime or a mixture of divided lime and carbon. Preferably, however, I first introduce a chargeof ,lime and then a charge of carbon. rIhe carbon used is preferably pure, though coal or colic free from sulfur may be used. As the material or materials mentioned are introduced it or they mingle with the reduced ore flowing from the clnimber 14 to theelectric chamber 19 and in IIO 4o doors 44 in the basin passing through'this chamber are sub'ected tothe 'physical effects of a series of e ectric arcs, W' ich physical effects I understand to be,4 first,

electrolytic action,

the arcs forming the due to the mechanical action :created by the lines of force passing between the electrodes the generated gases in ro of the arcs; fourth,- thosedue to the vibra- 'of force at' the resent tory mechanical action created by the lines passing between,` the electrodes of the arcs when an alternating current is employed; iifth, those due to ,such chemical actions as can only take place in the resence of an electric arc, and, generally, to a l eii'ects comprehended Within the broadA term physical effcctsof an electric arc, many of which time are not understood, the`=iina result being, a separation of the metallic iron from the impurities present.- such as. silicon, phos horus, and .other bodies-and' a chemica combination of the carbon with the introduced lime and other it will generate bodies separated from the iron ore.'

Sofar as I am at present able to discover there is formed calcium carbid, silicon ycarbid, as well as a body which appears to be of calcium, silicon, and carbon` composed andwhich actshke calcium carbid in that a gas when subjected to the action of water, but has the characteristics, soA faras hardness is concerned, of. silicon carbid'.v 4

As the materialspassthrough the electric y chamber' the iron, bein [of the greatest specific g'ravity, reaches t e lowest level and lsettles inthe basin 22, the otheriiuid materials ldepositing uponv the iron, from whence .they may bedrawn ofl-l through 22. After'the metal has been allowed to settle for a short space` of time it is drawn. oi through the trough-'like certain "amount chamber..--

= s'ired-to convert subjected to the oxidizingaction of an air- Ablast delivered through the pipe 31 until the passage 33 land deposited on the hearth 29 in the ch' mber 27 as Athe iron-in its assage throng the electric vchamber 19 will a sorb a of the carbon introduced through the hopper 38, and should it be detheiron into steel it is then metal oi' the hearth pro ortion ocarbon.

,f en it is desired 29 shows the required `metallic state-and-'in small pieces throu h the hopper 38 The combination is effected jas A the metals pass between the electrodes in the electric chamber.'

furnace is employed in the Where the those due tothe extremelyI high. temperature produced; second, those due' toelectroly'te'; third,.those v metal,

4purpose of removing yt are broken up b manufacture oi` glass, the sand and luxare introduced directly into the reducing-chamrber 14 through the door 18 -and allowed togradually work their way down through the electric chamber to the basin 22. The basin in such case is formed of sufficient depth tfo allow the usual settling and planing of the glass-making materials, and while in the ba# sin 22 the material may be drawn from such basin for blowing or casting through the doors 44, or it may be drawn throu trough-like passage 33 into the cham er 27 and on to any suitable hearth 29.

Where the furnace is used asa glass-fur-v nace, the amount of. gas and air introduced into the oxidizing-chamber `is merely sufficient to maintain the melting heat Without producing any oxidizin action. l

The removable heart as described, irrespective ofthe' material under treatment,

may be removed or casting or otherwise.

It will be observed from the above description that the features of novelt improved rocess consist, first, in su 'ecting the ore body to be acted upon to a gra uallyincreasing temperature and at' the same time to' the action of the reducing-gases created within the furnace until the zone of highest of my temperature isreached; second, introducing into the highly-heated and reduced ore bodyat the zone of highest temperature the-metal flux, carbon, or,I other bod v'or bodies `'with whichv he reduced. orebo y is to be combined; third, subjecting the lhighly-heated and reduced ore body, accompaniedjby the itisvto be combinedto the'ph an electric arc or arcs fora s tionsvof such bodies ;l fourth, separatingft7l gvity the differentl bodies produced, an h, subjecting the iron-carbon" compounds obtained within the lfurnace;structure/to the action :of an oxidizinglatnosphere'for the the contained carbon.

e wholeor apart `of m0,. carbon, iiux, or other body withwhich scaleiect of z cicnttime'to bring about the required chemicalcombinai' In carrying out the'p'rocess aboverlscribed I havel observed; products are evolved, through the reducing .t 'e heat present and set free hydrogen, w

theref re' permits of the treatment in 'the iur-v nace escribed 'of ores containingahgh perat various volatile wie@ -Hffnasslna and calcnnng'chainbers' ich combines with any sul-Y to lform sulurated hydrogen, and

centage of' sulfur-such, for instance', -asiron sulidsfwhich hithertov have fnotjbeen', successully treated further'g-that'where an ex# cess'cf carbon isus'ed carbonio 'O xid is gener gas yo rmixed with oxygen and burned the reducingchamber an oxidizing# chamber; further, as before stated, I have noticed-the presence of other gases. 'i

" By the term fcombining body as used in 'if drawn off as illuminating f.

While therein, in subjecting said bodies to the consists in moving a reduced ore body and `when subjected to the physical effects of an this specification I wish to have it underl stood that I include any body or bodies, either in the form of a gas, liquid, o solid, which will enter into chemical combination with the metal treated when exposed to the physical effects of an electric arc. I, however, do not include in this description and make noclaim for the. introduction of air at the temperature of the atmosphere or heated or such gases as are due to decomposition of fuel when such fuel is employed for heating the furnace, as such bodies are' in no respectl an important factorin carrying out the process specified in this application.

Having therefore described my invention, I claim- 1. The' hereindescribed process which consists in first reducing the ore, then introducing a combining body, then subjecting said bodies While in motion to the effects of an electric arc. v

2. The herein -described process which consists in first reducing the ore, then moving such reduced ore and a combining body through a zone of highl temperature and effects of an electric arc.

3. The herein described process which a combining body separately into a zone of high temperature and while therein, subjecting them to theeffects of an electric are.

4. rlhe herein -described process which consists in first partially reducing the ore in the presence of a flux, then subjecting said reduced and fluxed ore body to the physical effects of an electric arc and simultaneously to the action of a body fed into the reduced ore, and which when subjected to the physical effects of an electric arc will combine with the fluxing material carried by said reduced ore body.

5. The herein described process which consists in first calcimng, then fluxmg, then reducing, then subjecting said `treated ore While moving to the physical effects of an electric arc and simultaneously to the action of a body fed into the reduced ore, and which electric arc will chemically combine with bodies derived from said ore body.

6. `The herein-described process which consists in first partially reducing the ore, then subjecting said reduced ore to the physical effects of an electric arc and simultaneously to the action of a body fed into the reduced ore, and which when subjected to the physical effects of an electric arc will chemically combine with said reduced ore body and finally subjecting the metal derived from the orel body to the action of an oxidizing atmosphere.

7. The herein-described process which consists in'first reducing the ore, then introdu'cing a flux, then introducing a carboni body, and simultaneously causing the mixture to be subjected to the physical effects of an electric arc.

8. The hereindescribed process which consists in first partially reducing the ore, then subjecting said redued ore to the physical effects of an electric are and simultaneously to the action of a body which when subjectedto the physical effects of an electric arc will chemically combine with the reduced ore body, then separating the metal by gravity from its accompanying bodies' and finally subjecting the metal to the action of an oxidizing atmosphere.

9. The hereindescribed process which consists in subjecting the ore u'nder treatment to a gradually-increasing temperature and to the action of gases generated `within the furnace structure whereby the ore is partially reduced, then subjecting the reduced ore to the physical effects of an electric arc and simultaneously therewith to the action of a body or bodies fed into the reduced ore, and which when subjected to the physical effects of an electric arc will chemically combine with or react upon the bodies derived from the reduced ore body.

10. The herein-described process which consists in first reducing, then introducing into the reduced ore, a body or bodies which will chemically combine with it at a definite temperature, and simultaneously subjecting said combined bodies to the physical effects of an electric are or arcs.

1l. The herein-described process which consists in first reducing an ore in an atmosphere containing gases generated by the physical effects of an electric. arc upon a reduced ore body and a body of carbon, then subjecting the reduced ore while moving 'to the physical effects of an electric arc, and simultaneously to the action ol a scparatelye introduced body which when subjected to the Physical effects of an electric arc will chemically combine with said rcduccd ore body.

12. The herein-described process which consists in first reducing the ore, then subjecting such reduced ore to the physical effects of au electric ar and simultaneously to the action of a body fed into the reduced ore, which when subjected to the physical effects of an elect ric arc will chemically combine with said reduced ore. body, and finally subjecting the metal derived from the orc body to the action of an oxidizing atmosphere and introduced air-blasts.

13. A step in the described process which consists in subjecting thc ore body to the combined effects of a gradually-increasing temperature and gases produced by thc physical effects of a high-ten'iperalure electric arc, acting upon the ore body treated and odies introduced into the ore-bdy.

14. A step in the process which consists in IOC IOS

f subj ectingV an ore body to the action of gases -evo consistsl infirst subjecting the ore to the action'of'a reducing atmosphere and chemical bodies then subjecting said reduced ore. to the physical effects of an electric arc and simultaneously to the action. of a body fed into the reduced ore, and Which Will combine therewithl When subjected to the physical eifects of an electric arc.

16. The hereindescribed process which consists in first partially reducing the ore, then causing the said reduced ore to moveby gravity and simultaneously subjecting. said jected to the physical effects l 17. The hereinfdescribed l consists in subjecting a partia ly-reduced ore movingbody of .ore to the physical eiiects of an electric arc and a combining body fed into the reduced ore atthe time when itis sub- Of an electric arc. rocess which body while at a high temperature simultaneously tothe physical effects of an electric arc anda combining body introduced at such time.

. 1S.`,The vherein described rocess` which consistsv in first artially re ucing an ore body, moving sald ore body While heated into the zone of action of an electric arc and simultaneously subjecting said body to the action of a simultaneously-introduced cmwith the ore when both bodies are subjectedl to the physical effects of an electric arc.

21. The herein described process which consists in reducing an ore body, said ore body in areduced state to-iiow into azone Where it may bel subjected tothe physical action oi an electric arc, and continuously feeding into said flowing reduced ore in said zone, a body which Will combine with said reduced ore insaid zone and under the conditions present in said zone, created by the electric arc. V

In testimony whereof l affix my signature in the presence of two Witnesses. v

GEoRGE u.isiutmluIN.`

Witnesses:

J. E. Pia-Anson,` FRANK O'Coruvon.l

causing 

